Longwall mining system



June 22, 1965 K. w. STALKER 3,190,596

LoNGwALL MINING SYSTEM Filed Jan. 14, 1965 2 Sheets-Sheet l June 22, 1965 K. w. STALKER 3,190,696 LONGWALL MINING SYSTEM Filed Jan. 14, 1963 2 Sheets-Sheet 2 l ATTO @Ys Y eration, effected by advance of United States Parent O 3,190,696 LNGWALL MlNlNG SYSTEM Kenneth W. Stalker, Western Springs, lll., assigner to Goodman Manufacturing (Company, Chicago, lil., a corporation ot Iliinois Filed lan. 14, 1963, Ser. No. 251,316 6 Claims. (El. 299-11) This invention relates to improvements in mining sys- 4tems and more particularly relates to `a mechanical mining system for continuously mining and loading coal by the longwall method.

A principal object of the present invention is to provide an improved form of longwall mining system in which a face is alternately driven -along a block `of coal between two headings andthe face driving Ioperation is eilected by a multiple boring type Vof continuous mining machine, short enough to turn around in conventional width headlngs.

Another 'object of the invention is to provide an improved form of mining system for mining blocks of coal in a continuous operation in which the block of coal is mined rst in one direction and then in the opposite direction from `one heading to the other and in which maerial collecting and conveying means are carried in each heading to collect and` load the mined'material and to transfer lthe mined material -to the heading to be carried away along the heading, and in which the mining and loading operation is carried out by a multiple boring type of continuous mining machine short enough to turn around in a :standard width heading and `scraping or bulldozing the upstanding cusps from the mine door.

A further object of the invention is to provide an improved form of mining and loading system for driving a longwall face from one heading to another by the use of a multiple boring continuous mining machine, in which the iloor is maintained level and the upstanding cusps are removed from the door by a scraping or bulldozing opthe machine during mining, and in which a trimming and pick-up loader follows the continuous mining machine .andserves to trim the depending cusps from the roof and to trim the iloor along the mine face and load the trimmed' material all while the mined material is continuously loaded onto the cusp trimming and pick-up loader.

Still another object ofthe invention is to provide yan improved form `of mining system particularlyv adapted for longwall mining in which the mining operation is per `formed by a continuous mining machine of the boring type, loading yonto `a pick-up loader, and in which the cusp trimming `operation is effected by cutting devices carried by and powered from the pick-up loader.

These and other objects 4.of the invention will appear from time to time as the following specification proceeds and with reference 4to the accompanying drawings wherein:

FIGURE l is a diagrammatic view or map of a section of a mine, illustrating lone form in which the mining system ofthe invention may be carried out;

FIGURE 2 is a diagrammatic sectional view taken substantially along line 2`2 of FIGURE l;

' FIGURE 3 is a diagrammatic View of a section of a mine showing the completion of the driving or" a longwall face, with the continuous mining machine turning around in the heading and moving into position to cut a next succeeding longwall face; and

FIGURE 4 is a diagrammmatic plan view of a section Iof a mine, showing the roof supports advanced to the face and the cusp trimming and pick-up loader withdgawn, and showing the continuous mining machine at the start of a next succeedinglongwall face driving operation.

Patented .lune 22, 1965 ln the embodiment of the invention illustrated in the drawings, l have diagrammaticallyshown in FIGURE 1 a section of :a mine, to illustrate a partially driven longwall face, driven in .accordance with the principles of the present invention. As .shown in FIGURE l, an area or block Iof coal I@ is bounded on its opposite sides by the ribsof parallel headings or entries 11 .and 12. The roofs Iof the entries are supported by the usual props 13 4and cross beams 14, which are withdrawn as the longwall face is advanced and the mined area is caved.

I have also `shown a part of a previously driven longwall face 16 and have shown `a multiple boring type of continuous mining machine 17 driving a next succeeding longwall face 18. The roof in advance of the longwall face is supported by self-advancing hydraulic roof sup- Y porting unit-s 29 spaced closely `adjacent the longwall face 1d and extending for the length of the face, prior to driving the face, to support the roof while the face is being driven and to allow the roof to cave behind the jacks. As shown in :FIGURE l, the roof supporting units Zd are advanced during the face driving opera-tion to support lthe roof closely adjacent the mining and loading Larea, and are Iadvanced up to the face upon the completion of the driving lon one face and the initiation of the driving of a next succeeding face (see FIGURE 4).

The roof supporting units 2li may be self-advancing units in which roof beams 2l are held in supporting engagement with the roof by hydraulic jacks generally indicated by reference character 22. The hydraulic jacks 22 may be mounted on a base 23 and may be advanced by other hydraulic jacks (not shown) in a manner well known -to those skilled in the art, and no part of the present invention, so not herein shown or described further. A hydraulic power unit for the jacks (not shown) may be lkept in either one of the headings 111 or 12. The selfadvancing roof supporting unit is now commonly used in England and is known as the Dowdy Roofmaster and is no part of the present invention so need not herein be shown or described further.- The roof supporting units provide positive support for the roofV along the longwall face and accommodate the roof to cave behind the units, the caving being conventional in longwall mining systems.

The continuous mining machine 17, driving the longwall faces, may be a multiple boring continuous mining machine (operating on the principles of the McKinley type mining machine, and having a plurality of upper and lower aligned radial boring elements 2S cutting overlappinglbores in advance of the machine and a scaper or a bulldozer blade 26 extending across the front of the main frame of the machine, behind the rotary boringV elements, and scraping oil the opstanding cusps lef-t between the lower rotary boring elements and upstanding from the mine door. The machine is supported on laterally spaced continuous ltraction tread devices 27, which `serve to advance the rotary boring elements into the working face and at the same time providethe power to force the bulldozer blade 2d to break oil the upstanding cusps and level the mine door.

The continuous mining machine 17 has a relatively short conveyor 2? picking up the mined material and conveying the material fordischarge onto a bridge conveyortl, in material receiving relation with respect to the conveyor 29. The bridge conveyor 3d has a discharge end in position to load the mined material onto a conveyor 31 or a pick-up loader 32. The pick-up loader 32 in turn discharges into a series of mobile cascading conveyors 33, advancing with the continuous mining machine 17, as the face is driven. The cascading conveyors 33 are shown in FIGURE l as extending into and along the heading 12. The terminal cascading conveyor discharges onto a bridge conveyor 35, in cuttings discharge relation with respect to a conveyor S6, extending along the heading 12 to a main entry (not shown), where it may discharge onto shuttle cars, a main belt conveyor or any other suitable material transporting means.

The conveyor 36 may be an extensible belt conveyor, extended along the heading to carry away material from the initial longwall face and retractibly movable along the heading as the block of coal between the headings 11 and 12 is mined.

it should be understood from FIGURE 1 of the drawings, that a conveyor 36 extends along each heading 11 and 12 and that pick-up loaders 32 and cascading conveyors 33 are provided in each heading, the pick-up loaders and cascading conveyors not in use being stored in the heading until the completion of one longwall face driving operation and the initiation of a next succeeding longwall face driving operation.

The pick-up loader 32 is shown as being mounted on laterally spaced continuous traction tread devices 39, which advance the loader with the continuous mining machine 17 and the bridge conveyor 3), to maintain the pick-up loader in cuttings receiving relation with respect to the bridge conveyor. The pick-up loader has the usual conveyor extending therealong, extending upwardly from the ground to pick-up loose material from the ground left behind the continuous mining machine 17, as it advances, and also has a pair of upper cutter bars 4t) suitably supported in advance of the loader for trimming the roof behind the continuous miner. The inner cutter bar 4Q serves to cut a slot 54 along the newly driven face at roof level. The pick-up loader 32 further has a relatively long deflector 41 pivoted to the outer side thereof and suitably held in position and extending outwardly for substantially the width of the place being cut, for progressing the mined material to be picked up by the conveyor 31, during advance of the pick-up loader. The deilector 41 has an outer lower trimmer bar 43 pivotally mounted thereon to trim any material from the tloor left after the bulldozing operation, and also serving to load any loose material on the floor onto the conveyor 31. The pick-up loader 32 also has an inner deflector 45 shorter than the deilector 41 and extending to the longwall face for progressing the loose material on the floor to be picked up by said loader. The delector 45 has a cutter bar 46 mounted thereon and projecting therefrom a distance sufficient to cut a slot 47 in the longwall face at oor level as well as to trim any cusps that may be left by the bulldozer blade 26, and to provide a clean floor to the face. The material mined by the cutter bars 43 and 46' is retained by the detlectors 41 and 45 to be crowded into the receiving end of the conveyor 31 as said conveyor advances with the bridge conveyor 30 and continuous mining machine. The cutter bars 40, 411 and 43 and 46 may be well known forms of chain carrying cutter bars suitably driven and supported and are no part of the present invention so not herein to be shown or described in detail. It should here be noted that the cutting done by the trimmer bars 40, 43 and 46 is a light cutting operation and that very little power is required to drive the cutter chains (not shown) about the cutter bars.

The cascading conveyors 33 are individual self-power conveyors having hoppers 48 at their forward ends and mounted on wheels 49, which may be power driven. One conveyor 33 extends over the hopper of the next succeeding conveyor and may be supported thereon. The tail end conveyor 33 is shown as being supported on wheels 50 at its discharge end and as having the bridge conveyor 35 mounted thereon, for discharging the mined material onto the conveyor 36.

In initiating a longwall face driving operation, assuming the self-propelled roof supporting units Ztl have been advanced to the longwall face, as for example the face 1d shown in the lett hand side of FEGURE 1, and

have been so advanced for the entire length of the face to solidly support the roof back of the face, and permit the root back of the root supporting units to cave, the continuous mining machine may be moved along the hea-ding 12 and turned diagonally to face the left hand ri-b of said heading. The mining machine 17 is advanced to initially diagonally attack the left hand rib of the heading The boring elements 25, 25 being in operation, the continuous mining machine 17 is propelled by its traction tread devices Z7, to feed the boring elements into the rib, and is turned as it is advanced to mine parallel to the longwall face 16 with the outer margins of the bore intersecting the face to remove the face by boring. lluring the initial face driving operation as the continuous mining machine diagonally drives into the rib tace, the machine may load directly onto the pick-up conveyor 32. As the longwall face advances, however, the bridge conveyor may be connected to the continuous min ing machine and load into the pick-up conveyor 32.

The lower boring elements 25 will leave an upwardly projecting central cusp 51 between said boring elements and outer cusps S2 and 53. These cusps are scraped or dozed from the door by the bulldozer blade 26, for the width of said bulldozer blade, which is substantially the width of the machine.

As the machine advances along the face, the pick-up loader 32 will advance therewith and the upper trimmer bars 44 will trim the cusps depending from the mine roof to provide a level roof for the beams 21 of the roof supporting units 2b. The inner upper trimmer bar 40 will `also cut a slot S4 into and along the longwall face. The lower cutter bars 43 and 45 will trim any portion of the upstanding cusps 51, 52 and 53 remaining at floor level. The left hand lower trimmer bar will also cut a slot 47 ,along the longwall face at floor level for the length of the face. The lower trimmer bars 43 and 46, besides trimming the lower cusps 52 and 53, will progress the trimmed material and any material falling to the ground onto the receiving end of the pick-up loader 32 in cooperation with the deflectors 41 and 45. The dellector 41 will also tend to keep the mined material toward the longwall tace 18 and the deector 4S and trimmer bar 46 will tend to progress the mined material onto the pick-up loader 32 and to prevent an undue amount of accumulation of material in advance of said pick-up loader 32.

The slots 47 and 54 cut along the new face, besides trimming, the floor and roof reduce the amount of material mined at the outside of the working face, during the next succeeding mining operation and thus reduce the accumulation of material al-ong the iloor at the outside of the pick-up loader 32. The pick-up loader 32 moving along the newly driven longwall face 18 and the cascading conveyors 33 following said pick-up loader will load the material as it is mined and transfer the material into the heading 12 for discharge onto the conveyor 36. This longwall face operation will continue until the continuous mining machine approaches the right hand rib of the left hand heading 11. The continuous mining machine will then turn slightly inwardly to position the machine to be turned around in the heading 11 at the end of the face driving operation.

As the longwall face is advanced, the roof supporting i units 20, 29 are advanced into close proximity to the cascading conveyors 33 to support the roof as close as possible during the entire mining operation, as shown in FIGURE 1.

At the completion of a face driving operation, the bridge` conveyor 3) is disconnected from the continuous mining machine 17 and the cascading conveyors 33 are withdrawn from the longwall face into the heading 12 along the side of the conveyor 36 and are stored along side of said conveyor for a succeeding longwall face driving and loading operation.

' During this operation, the roof supporting units 20, 20 may be advanced close to the newly driven face 18 to support the roof yalong, this face for the length thereof. and to allow the roof back of said roof supporting units to cave as shown in FIGURE 4.

The continuous mining machine may thenbe moved into the heading lll and backed towards the stored pickup l-oader 32. The pick-up loader 32 .and cascading conveyors 33 may then be moved along the heading l1 behind the continuous mining machine.

The continuous mining machine 17 being at an angle with respect to the rib of the heading is advanced diagonally into the rib to initiate a next succeeding longwall face 18a, the conveyor of the continuous miningmachine loading directly onto the pick-up conveyor 32 during the initialv face driving operation. When the machine 17 advances into position parallel to the face 18, the bridge conveyor 30 may be attached thereto and the pick-up conveyor 32 may be moved int-o position and its cutter bars may be adjusted to trim the roof and floor of the new working place. The mining and loading operation may then lcontinue from left to right in the previously described manner. The face driving and loading operation may then be :alternately repeated from right to left and left to right until the entire block of coal lit may be mined out.

It may be seen from the foregoing that a simple and improved system of continuous mining a long faceof coal has been provided, utilizing a continuous mining machine of the boring type which has been shortened to the extent that it can turn around in headings of a conventional width 'to irst drive a face in `one direction and then drive a face in an opposite direction, all while the mined material is lbeing continuously loaded by the pick-up loader and cascading conveyors, following the continuous mining machine.

It may further be seen that a simple and relatively inexpensive mining unit may be used for the face driving operation, and with this unit the iloor is leveled by the bulldozer blade extending across the front of the unit, and the remaining cusps at roof and lloor level are trimmed by the trimmer bars 4t), dit and t3 and 46, the trimmer bar 46 and the inner 4trimmer bar 4@ at the same time mining the slots 47 and 54 to provide clean relatively level roof and floor lines for the next succeeding mining operation, and to reduce the material mined along the Iiloor during the trimming operation at the outer side of the bore, and to thereby reduce the -amount of material at the -outside of the bore, to be moved inwardly toward the conveyor.

It should be understood that while the mining system described is particularly advantageous for mining coal, that it may be used to advantage in mining and loading various other materials that can be mined by a continuous mining machine, as for example, potash, gypsum and salt.

While I have herein shown and described one form inv which the invention may be embodied, it may readily be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof as deiined by the claims appended hereto.

I claim as my invention:

1. A system of mining a block of coal between two headings comprising the steps of supporting the roof along the face of the block between the headings closely adjacent the face by mechanical roof supporting units, driving a longwall face by multiple boring operation initiating at the rib of the first heading of said two headings and during this driving operation following the multiple boring operation with a rst series of cascading conveyors extending along the iirst heading and following the multiple boring operation along the longwall face and carrying away the mined material and loading the mined material in the first heading, storing a second series of cascading conveyors in the second of said headings, advancing the roof supporting units toward the face as the multiple boring operation progresses and during the boring operation removing the cusps between the boring-devices to provide a level oor and roof, and at the termination of the face driving operation withdrawing theflrst series of cascading conveyors into the rst heading, and advancing the roof supporting unitstowards the newly driven face and at the same time reversing the multiple boring operation followed by the second series of cascading conveyors for the full extent of the face driving operation.

2. In a method of mining a block of coal between rst and second parallel spaced headings, driving a longwall face between the two headings with a multiple boring type continuous mining machine and during the boring operation bulldozing the upstanding cusps left along the oor to provide a level oor surface, loading the mined and bulldozed material and transferring the loaded material to conveyor means following the multiple boring continuous mining machine, conveying the mined material along the first heading and transferring the material to loading means in the first heading, and at the termination of the face driving operation withdrawing the conveying means back to the iirst heading and turning the multiple boring mining machine in the second heading and then initiating a next succeeding continuous boring mining and loading operation from the rib of the second heading and driving a next succeeding longwall face parallel to the face just driven by the multiple boring machine, while following the driving operation by conveying means extended from the second heading by the multiple boring continuous mining machine.

3. A system of driving a longwall face between rst and second headings comprising the steps of providing mechanical roof supporting units and supporting the roof closely adjacent the longwall face by the roof supporting units, providing a series of cascading conveyors in each heading, providing a single multiple boring continuous mining machine capable of entirely turning around in each heading, driving the face by the multiple boring machine from the rib of the first heading for substantially extending from the lirst heading, and advancing the roof supporting units toward the new face driven by the multiple boring continuous mining machine as the driving operation continues and at the termination of the face driving operation withdrawing the cascading conveyors into the irst heading, advancing the roof supporting units to the newly driven face, turning the multiple boring continuous mining machine around in the second heading and driving a new longwall face from the second heading while following the driving operation by the cascading conveyors stored in the second heading and while advancing the roof supporting units as Ithe driving operation progresses.

4. In a system of mining a block of coal between parallel first and second headings, the steps of providing a continuous mining machine in the iirst heading, providing a series :of cascading conveyors in each heading and providing a separate pick-up loader in each heading in discharge relation with respect to said cascading conveyors, supporting the roof along the face of the block of coal from one heading to the other by mechanical roof supboring mining operation by the continuous mining machine from the iirst heading and driving the longwall face along the block of coal from the iirst heading to the second heading, and during this driving operation following the continuous mining machine by the pick-up loader and cascading conveyors provided in the first heading and advancing the roof supporting units toward the face as the face is driven, and at the termination of the longwall face driving operation withdrawing the cascading conveyors and pick-up loader to the first heading, continuing travel of the continuous mining machine into the second heading, turning the continuous mining machine around in the second heading, advancing the roof supporting units into juxtaposition to the newly driven face and then performing a next succeeding longwall face driving and loading operation with the previously stored pick-up loader and cascading conveyors advancing from the second heading and following the continuous mining machine.

5. A mining system in accordance with claim l wherein the continuous mining machine is a multiple boring mining machine and leaves cusps upstanding from the mine oor and depending from the mine roof, between the boring heads, wherein the continuous mining machine bulldozes the cusps upstanding from the floor during the progresh sion of the mining operation, and wherein the pick-up loader trims the cusps depending from the roof and the remaining cusps on the tloor during advance of the pickup loader With the continuous mining machine.

6. In a method of mining a block of coal between two parallel spaced first and second headings, driving a longwall face between the two headings with a multiple boring type continuous mining machine and during the boring operation bulldozing the upstanding cusps left along the iloor to provide a level iloor surface, loading the mined and bulldozed material and transferring the loaded material to conveyor means following the multiple boring continuous mining machine and extending from the first heading, conveying the mined material along the newly driven face to and along the first heading and transferring the material to loading means in the rst heading, and

at the termination of the face driving operation withdrawing the conveying means back into the iirst heading andturning the multiple boring mining machine around in the second heading and then initiating a next succeeding continuous boring mining and loading operation from the rib of the second heading and driving a next succeeding longwall face, parallel to the face just driven, while following the driving operation by conveying means extended from the second heading along the longwall face by the multiple boring continuous mining machine and during the boring operation cutting slots in the new rib at ioor and roof level to provide a clean floor and roof for a next succeeding face driving operation and to reduce the cuttings along the oor at the outer side of the pick-up loader during the next succeeding face driving operation.

References Cited by the Examiner UNlTED STATES PATENTS 2,651,513 9/53 Ramsay. 2,694,562 11/ 54 Snyder et al. 2,705,626 4/ 55 Ball.

2,778,622 1/ 57 Reis.

2,780,451 2/ 57 Alspaugh et al. 2,816,747 12/57 Ball.

OTHER REFERENCES Mining Congress Journal, October 1959, page 91.

BENJAMN HERSH, Primary Examiner. 

1. A SYSTEM OF MINING A BLOCK OF COAL BETWEEN TWO HEADINGS COMPRISING THE STEPS OF SUPPORTING THE ROOF ALONG THE FACE OF THE BLOCK BETWEEN THE HEADINGS CLOSELY ADJACENT THE FACE BY MECHANICAL ROOF SUPPORTING UNITS, DRIVING A LONGWALL FACE BY MULTIPLE BORING OPERATION INITIATING AT THE RIB OF THE FIRST HEADING OF SAID TWO HEADINGS AND DURING THIS DRIVING OPERATION FOLLOWING THE MULTIPLE BORING OPERATION WITH A FIRST SERIES OF CASCADING CONVEYORS EXTENDING ALONG THE FIRST HEADING AND FOLLOWING THE MULTIPLE BORING OPERATION ALONG THE LONGWALL FACE AND CARRYING AWAY THE MINED MATERIAL AND LOADING THE MINED MATERIAL IN THE FIRST HEADING, STORING A SECOND SERIES OF CASCADING CONVEYORS IN THE SECOND OF SAID HEADINGS, ADVANCING THE ROOF SUPPORTING UNITS TOWARD THE FACE AS THE MULTIPLE BORING OPERATION PROGRESSES AND DURING THE BORING OPERATION REMOVING THE CUSPS BETWEEN THE BORING DEVICES TO PROVIDE A LEVEL FLOOR AND ROOF, AND AT THE TERMINATION OF THE FACE DRIVING OPERATION WITHDRAWING THE FIRST SERIES OF CASCADING CONVEYORS INTO THE FIRST HEADING, AND ADVANCING THE ROOF SUPPORTING UNITS TOWARDS THE NEWLY DRIVEN FACE AND AT THE SAME TIME REVERSING THE MULTIPLE BORING OPERATION FOLLOWED BY THE SECOND SERIES OF CASCADING CONVEYORS FOR THE FULL EXTENT OF THE FACE DRIVING OPERATION. 